:::: Interesting configuration Gene. There's just one thing you neglected to
tell us............
......How well does it work? Tell us the kind of stuff you can work on the
air.
BILL K2OWR
----- Original Message -----
From: "Gene Fuller" <w2lu@rochester.rr.com>
To: <rlvz@aol.com>; <towertalk@contesting.com>
Sent: Saturday, January 02, 2010 18:04
Subject: Re: [TowerTalk] Half sloper recommedations needed
> Hi Dick -
>
> I can just tell you my experience. I"m using 3 quarterwave slopers from a
> 100 foot tower on 160. A rely box at the top of the tower selects which of
> the three is on the coax. Coax shield is connected to the top of tower.
> Since it's about 200 feet from the tower to the station I have a "line
> flattener" at the base of the tower tunerd for best SWR at the station.-
> Also switching from RG-213 comming down the tower to 75 ohm hard line to
> the
> station). I made no attempt to tune/resonate the sloper. Although the
> "F/B"
> ratio may only be a very few db I figure it's worth it to have more than
> one. Wouldn't you think it was great if you could have 4 or 5 KW instead
> of
> 1.5 for the price of an extra wire and a relay ??? Since I have 3 bent
> halfwaves on 80 ( operated as one driven and two reflectors) I have 3
> quarterwaves on 160 (140 feet each) placed between the 80m halfwaves.
> Bottom
> line - both the 160m quarterwaves and the 80m halfwaves seem to work very
> well. I really don't know if my 7-60 MHz LP on the top of the tower is in
> the picture. The 40 foot 160m slopers are probably somewhat acting as
> aditional reflectors on 80. They were originally installed as 80 m
> reflectors when what are now 80m bent vertical dipoles were actually 80m
> sloping dipoles. Running the bottom half of the sloping dipoles back
> towards
> the bottom of the tower was VERY worthwhile - canceled the horizontal
> component bringing the rad angle from 28 down to 18 degrees. One driven
> and
> two reflectors is only good for about 4 dbi but the 18 degree takeoff more
> than makes up for the low gain.
>
> Good luck with whatever you wind up with.
>
> Gene / W2LU
>
>
> ----- Original Message -----
> From: <rlvz@aol.com>
> To: <towertalk@contesting.com>
> Sent: Thursday, December 31, 2009 4:27 PM
> Subject: [TowerTalk] Half sloper recommedations needed
>
>
>> Hi Guys-
>>
>> I'd appreciate your recommendations on building a Half Sloper for 160-m.
>> I realize that some folk have had excellent results with Half Slopers
>> and
>> others have had terrible results with them! That's why I'm asking for
>> advise on how to construct my Half Sloper!
>>
>> Question 1: Most antenna articles say when constructing an Inv. Vee is
>> to
>> keep the minimum angle between wires at 90 degrees or greater. Since
>> Half
>> Slopers almost never have a 90 degree angle between the sloper wire and
>> the
>> tower is this one reason why many Half Slopers don't work very well...
>> lots
>> of signal cancellation?
>>
>> Question 2: I have a 90' tower with a Tribander on top which makes it
>> very
>> close to a 1/4 wave for 160-m. I installed an Inverted L on this tower
>> with 85' vertical and the Inv. L radiating efficiency is very poor due
>> to
>> heavy coupling between the Inverted L and the tower. (some models say
>> that
>> alot of RF is shorted right to ground!) Therefore, I am thinking of
>> going
>> with a Half Sloper connected near the top of the 90' tower with the
>> sloper
>> wire running NE towards Europe. If I anchor the end of the sloper wire
>> about
>> 200' from the tower the angle is only going to be about 45 degrees. Do
>> you think this will work any better towards Europe than my heavily
>> coupled
>> and inefficient Inv. L? (another weakness with my Inv. L is that I have
>> a
>> minimal radial system as it must be pulled up each Spring).
>>
>> Question 3: Rather than build the Half Sloper on the 90' tower would an
>> Inv. L on my 60' tower with 55' vertical and the rest horizontal running
>> NE
>> towards Europe likely outperform the Half Sloper at 90' towards
>> Europe...
>> keeping in mind that this is a temporary antenna so I can only put down
>> a
>> minimal radial system as the radials need to be removed in Spring.
>>
>> I realize that I'm likely to get a variety of opinions on this and that
>> is
>> fine! Please let me know which of the above options you believe is most
>> likely to provide the best 160-m. signal towards Europe.
>>
>> Happy New Year!
>>
>> 73,
>> Dick- K9OM
>> Edgewater, Florida
>>
>> _______________________________________________
>>
>>
>>
>> _______________________________________________
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>> TowerTalk@contesting.com
>> http://lists.contesting.com/mailman/listinfo/towertalk
>
> _______________________________________________
>
>
>
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